1. Field of the Invention
The present invention relates to the field of delayed coker units and more particularly, a system for covering the coke drum of a Delayed Coker Unit (DCU) and providing a drill stem guide.
2. Description of the Related Art
Conventional manual top unheading, makeshift or impromptu drill stem guides and often absent or crude covers have been used during DCU top unheading and coke cutting operations.
There are now several coke drum top unheading valves available in the commercial industrial market but only a few in use. Most DCUs continue to use manually bolted top heads and therefore manual top unheading. Many DCUs use some form of a drill stem guide collar but other installations do not. Drill stem guides seen on DCUs range from very crude contraptions built as an afterthought to more carefully constructed devices.
Somewhat similarly, a wide variety of top head covers, built for various purposes depending on the DCU operating conditions and requirements, are also seen. These covers are also typically simple and basic coverplates that are pinned or manually bolted to the top head and do not include any technique for controlled actuation or movement.